Honing machine



, y 1, 1941. 1H. J. CALDWELL 2.2 79 7 HONING' MACHINE Filed April 15,1959 4 Sheet-Shaet 2 July 1, 1941. H. J. CALDWELL HONING MACHINE FiledApril 13, 1939 4 Sheets-Sheet 3 NVEINTOICL/ g CZ Cam we m I @K V (ATTO@1575 July fl, 1941. J CALDWELL 2,247,479

HONING MACHINE Filed April 13, 1939 4 Sheets-Sheet 4 I i P41 PatentedJuly 1, 1941 HONING momma Harry J. Caldwell, asthma, 111., assignor toBarnes Drill Compan y, Rockford, 111., a corporation oi IllinoisApplication April 13, 1939, Serial No. 287,572

18 Claims. (01. 51-34) The invention relates to machines for honingcylindrical surfaces, and more particularly to honing machines of thehorizontal type.

Horizontal honing machines are used extensively in dressing the surfacesof work pieces which, because of their relatively great length, are mostconveniently operated on while held in a horizontal position. In thisoperation, relative rotation is imparted to the tool or hone and thework, while the supports which carry the tool and work aresimultaneously relatively reciprocated to traverse the tool repeatedlyfrom one end of the work piece to the other. In practice, only one ofthe supports is reciprocated, usually the tool support, and to this endthe reciprocable support is mounted on a horizontal guideway formovement toward and from the other support.

Movement of the reciprocatory support is eifected by power actuatedmeans of any suitable character. The power actuated means frequentlycomprises a motor which may be of the reversible type or which may bearranged to drive the support through a reversible drive mechanism. Ineither case it is essential that the reversal take place at exactly theright point in the reciprocatory cycle of the support in order to insureuniform action of the tool over the entire surface of the work piece andyet avoid overrunning the ends of the same.

One object of the present invention is to provide improved controlmechanism for controlling the reciprocation of the movable support of amachine of the above general character.

Another object is to provide mechanical con- 35 trol mechanism forhorizontal honing machines which, by reason of the novel and improvedconstruction of the moving parts to provide low inertia or momentlun andthereby minimize the shock or jar incident to the movement of the same,is quiet in action, reliable and accurate in operation, readilyadjustable to adapt the machine for operating on work pieces ofdiflerent length, and capable of standing up under the hard usage towhich such mechanism is necessarily subjected.

Still another object is to provide improved mechanical reciprocationcontrol mechanism which is universally adaptable for actuating eitherelectrical or hydraulic control devices.

A further object is to provide an improved reciprocation controlmechanism for horizontal honing machines particularly adapted tofacilitate the disassociation oi the tool and work upon completion ofthe honing operation.

Other objects and advantages of the invention will become apparent fromthe following detailed description of the preferred embodimentsillustrated in the accompanying drawings,

'5 in which:

Figure 1 is a plan view of a hydraulically operated horizontal honingmachine embodying the Tieatures of the invention. the hydraulicequipiment being shown diagrammatically.

Fig. 2 is a. fragmentary view of a preferred form of the controlmechanism showing one end of the control rod equipped with cam means foroperating a hydraulic valve. I I Fig. 3 is a sectional view taken alongthe line '15 'd-3 of Fig. 2 showing details of the control rod cam andthe valve operator detent means. Fig. 4 is a transverse sectional viewthrough the machine illustratedin Fig. l-showing the re- 'flationship ofthe control rod, the-cam means and 201 the control valve operatedthereby.

i Figs. 5 and 6 are sectional views taken along "the line 5-5 of Fig. 2showing the cam in difierent operating positions.

' Fig. 7 is a view similar to Fig. 2 but showing the control rodequipped for operating electrical switches. I

.' Fig. 8 is a vertical sectional view through the I control rodtakenalong the line 8-8 of Fig. '1

' rod acshowing the arrangement of the control tuating mechanism.

Fig. 9 is a sectional view taken along the line 9--9 of Fig. 7 showingdetails of the switch op- .eratingmechanism and the control rod andrestoring means.

Fig. 10 is a horizontal sectional view taken along the line ill-l0 ofFig. 7 showing details of the switch operating mechanism.

Fig. 11 is a .schematic diagram of the electrical control circuit of amachine embodying the control mechanism illustrated in Figs. 7 and 10.

For purposes of illustration, the invention has I been shown anddescribed herein as applied to a honing machine in which the toolsupport is reciprocated relative to a stationarily supported work pieceby hydraulically operated driving means, but it is-to be understood thatthe in- 'vention is readily applicable to other types of honingmachines. It is also to be understood that various modifications andadaptations in the form, construction and arrangement of partscomprising the improved reciprocation control mechanism may be made bythose skilled in the art without departing from the spirit and scope ofthe invention as expressed in the appended claims.

Referring to. Fig. 1 of the drawings, the machine selected to illustratethe invention comprises an elongated base 12 having an extension I: atone end constituting a work support. The base I2 is equipped with spacedparallel guide bars l2 (Fig. 4) which provide a guideway for areciprocatory head or tool support M (Fig, 1) on which is journalled aforwardly projecting spindle I5 adapted to carry a conventional honingtool It. A driving motor I! mounted on the tool support is arranged torotate the spindle through suitable gearing enclosed in a gear housingi8.

In performing a honing operation, the work piece is secured to the worksupport l3 and the honing tool It is traversed over the surface to behoned by movement of the tool support toward and from the work piece.Such movements are imparted to the tool support by power operated meansherein shown as comprising a pair of flexible tension members or cables19 and 20 anchored respectively to opposite ends of the support andwound in diflerent directions around a grooved cable drum 2| rotatablysupported at one end of the base l2. One of the cables, in this case thecable I9, is led directly to the cable dlrum while the other cable 20 iscarried over a sheave 22 Journaled at the opposite end of the base l2 sothat the cables act alternately to advance and retract the tool support,that is, to draw it forwardly and back on the guideway when the drum 2|is rotated first in one direction and then in the other direction.

In the exemplary machine, rotation of the cable drum 2! is eflected by areversible hydraulic motor M. The motor as herein shown is of the rotarytype, and is arranged to actuate the'drum through the medium of adriving mechanism including a worm 24 and cooperating worm wheel 25, thelatter being fast on a cross shaft 26 to which is keyed a pinion 21meshing with a gear 28 rigid with the drum. Pressure fluid is suppliedto the motor M by a variable delivery pump P through a suitablehydraulic circuit in which is interposed a pressure controlling valveV-l, a

stop valve V2, and a reversing valve V3, all of well known construction.An electric motor M-| is arranged to drive the pump P at substantiallyconstant speed, the output of pressure fluid to the hydraulic circuitbeing varied as required to regulate the speed of the motor M and thusthe rate of movement of the head M by manipulation of a manuallyoperable member 3 I. Starting and stopping of the motor M is controlledby the stop valve V--2 which may be operated manually as by a hand leverL, mechanically coupled with the valve through a suitable linkage 32, orby a solenoid SOL-l arranged to shift the valve plunger.

The direction of rotation of the motor M and consequently the directionof movement of the tool support It is controlled by the reversing valveV3. The reversing valve, as herein shown, is operated under control of apilot valve V4 arranged to control the flow of pressure fluid tooperating cylinders formed in opposite ends of the reversing valvecasing for the purpose of shifting the valve plunger to either of itstwo positions. An auxiliary. valve V--5 interposed between the pilotvalve and the reversing valve is effective when operated to preventoperation of the latter when the pilot valve is reversed at one end ofthe stroke ofv the reciprocatory support, thus causing-the support tomove beyond its normal working range to fully retracted position. Inthis way the tool is disassociated from the work at the end of thehoning operation.

As herein shown, the auxiliary valve V--5 is spring-biased to a normalopen position and is adapted to be operated by a solenoid SOL-2. Theenergizing circuit for the solenoid is controlled by a relay R-l throughthe medium of a switch R--ll closed when the relay is energized. RelayR-I, in turn, is connected in a circuit adapted to be completed byclosure of a switch SI which may be actuated manually or in any othersuitable manner. 8-! in the relay circuit is arranged to be operatedautomatically, as will be described hereinafter, to deenergize the relayRl and solenoid S-2, and thus prepare the machine for the next operatingcycle when the tool support has been fully retracted.

In the normal operation of the machine, the reversal of the direction ofmovement of the tool support at alternate ends of its working stroke iseflected by shifting the pilot valve V-4 between its alternate activepositions. The operation of this valve at the proper point in thereciprocatory cycle of the support is the function of the controlmechanism of the present invention. The operation may be effectedthrough a direct mechanical connection between the control mechanism andthe valve, or indirectly through the medium of solenoids SOL-4 and SOL4arranged to be energized selectively under control of the mechanism.

For either direct or indirect control of the pilot valve, the controlmechanism includes essentially 'an elongated control rod 33 extendingsubstantially parallel to the reciprocatory path of the tool support It.In the preferred forms illustrated in Figs. 2 and 7 of the drawings, thecontrol rod is rotatably supported for rocking motion in bearings formedin brackets 34 projecting laterally from the sides of the base l2adjacent the top of the base. One end of the control rod is equippedwith appropriate mechanism operative in rocking movements impartedthereto to actuate the pilot valve V-J directly through suitablemechanical linkage or indirectly through the medium of switches arrangedto control the solenoids SOL-3 and SOL-4. A preferred form of themechanism for operating the pilot valve directly, indicated generally bythe reference character 35, is shown in Figs. 2-6. Suitable mechanism 36for indirect operation of the pilot valve is shown in Figs. 7-10.

Suitable means is also provided for yieldably holding the control rod ina neutral position and for restoring it to such position after eachoperation. As herein shown, this means comprises an elongatedcross-member 31 (Fig. 2) extending transversely of the control rod andrigidly secured thereto in any suitable manner. Sockets formed is atopposite ends of the member seat spring- A normally closed switch toolsupport as an incident to its movement along the guideway. For thispurpose there is secured to the reciprocatory head l4 a horizontalbracket 4I- projecting laterally over the control rod 35 (Figs. 1 and9). A vertical stud 42 set in the end of the bracket carries on itslower end a. cam roller 43 adapted to coact with cam surfaces formed onradially projecting actuating members or arms 44, 45 and 48 rigidlysecured to the control rod.

As will be seen by reference to Fig. l. the actuating arms 44. and 45are spaced apart a substantial distance longitudinally of the rod. Thesearms define the limits of the working stroke of the tool, that is, therange of travel of the tool when operating upon a. work piece. In orderto provide for variation of the working stroke to accommodate workpieces of different length, both actuating arms are preferablyadiustably secured to the control rod as by set screws 41 (Fig. 8) eachof which is preferably formed with a reduced end portion 45 engaging ina groove 49 extending longitudinally of the control rod. One such grooveis provided for each actuating arm and these are so spaced that the armsare invariably held in the correct position relative to the cam roller48 carried by the head,

The third actuating arm 48 is located rearwardly of the arm 45 and inthe present instance serves to define the extreme limit of movement ofthe tool support toward retracted position. This arm is similar inconstruction to the arms 44 and 45 hereinbefore describedand if desiredmay be similarly adjustably secured to the control rod.

Referring more particularly to Figs. 1 and 2, the control rod actuatingarms terminate at their upper ends in elongated generally horizontalcross members 5i. 5! and 5!". The opposite ends of the cross-members arebeveled as at 52, 52 and 52 to form inclined cam surfaces for engagementby the cam roller 43. The cam surfaces of the actuating arms 44 and 45are faced in opposed directions as will be seen by reference to Fig. 1,so that the control rod will be rocked in opposite directions uponengagement of the respective cam surfaces by the roller 43. In otherwords, upon the engagement ofthe cam surface 52 the control rod isrocked in a clockwise direction as viewed in Figs. 5, 6, 8 and 9, whileengagement of the roller with the cam surface 52 rocks the control rodin a counterclockwise direction. The amplitude of this rocking movementdepends upon the form of the cam surface and the relative position ofthe actuating arms and is preferably relatively small.

The cross-member of the actuating arm 46 is formed with cam surfaces 52similar to the earns 52 and 52 and faced in the same direction as thelatter cam surfaces. It will be observed however (Fig. 1) that thecross-member Bi of the arm 46 is displaced angularly with respect to thecross-member of the arm 45 so that roller 43, upon engaging the cam 52',rocks the control rod to a limit position beyond the intermediateposition to which it was rocked by engagement with the cam 52*.

It will be seen from the foregoing that the control rod 33 is adapted tobe rocked from its neutral position to either of two limit positions orltO an intermediate position. The movement to one limit position iseffected by the approach of the tool head to the forward end of itsworking stroke while movement to theother limit position occurs as thetool head approaches its fully retracted position. The tool head onapproaching the rearward end ofits working stroke rocks the control rodto its intermediate position. 'Ilhe mechanisms by which these rockingmovements of the control rod are utilized to control the reciprocationof the tool support will now be described. a

When the control rod is to be utilized to operate the pilot valve V-4mechanically, the operating mechanism 35 provided for this P secomprises a generally segmental cam plate 5| (Figs. 2-6) having anintegrally formed collar Blthrough which extends a bore SI for thereception of the control rod. The cam is keyed or otherwise nonrotatablysecured to the control rod. A valve actuating member 52 having agenerally triangular body portion and an integrally formed elongated armis pivoted on a stationary bracket 64 secured to the side of the machineframe. A rigid link 85 connects the free end of the arm 83 with a crank66 fast on the movable member of the pilot valve V4 whereby movement, ofthe actuating member on its pivot is effective to operate the valve.

The pivotal axis of the actuating member is substantially parallel tothe axis of the control rod and spaced above the same so that thetriangular body portion of the member extends over the face of the cam6i. Mounted on the body portion on opposite sides of the cam are a pairof cam followers 67 and 68, preferably in the the form of rollers,adapted to be engaged alternately by the active areas of the side edgesof the cam. as the control rod is rocked about its axis. In this way,the actuating member is rocked to alternate valve operating positions.

The shape of the cam 6i and the spacing of the followers 61 and providesa degree of lost motion sumcient to enable the member 62 to remain ineither operated position after the control rod and cam return to neutralposition. This condition is illustrated in Fig. 5 in which the cam isshown in neutral position while the member 62 is in the position towhich it was previously operated by movement of the cam to the positionshown in dotted line. When the control rod is subsequently rocked in a.clockwise direc tion, as viewed in this figure, the active edge of thecam engages the follower 68 and positively rocks the member through anangle such as to shift the arm 83 to the dotted line position shown.This position is attained just as the control rod reaches itsintermediate position, and upon further movement of the control rodtoward its limit position, the roller 68 rides over the arcuate edgelill' of the cam, thus serving to hold the member in operating positionbut imparting no further movement thereto. Upon movement of the controlrod toward its .other limit position, the actuating member remainsstationary until the opposite active area of the cam engages thefollower 5i and rocks the member back to the position shown in Fig. 5.

Since the pilot valve must be maintained in operated position throughoutthe entire working stroke of the tool head, latch means is provided forholding the member 62 in operated position until it is positivelyshifted by the cam I, as above explained. To this end, a spring-presseddetent 69 (Fig. 3) is arranged to cooperate with suitable depressions 10formed in the inner face of the member 62. As here in shown, the detentGdcomprises a relatively short, generally cylindrical plunger slidabiysupported coaxially with the control rod 33 in a recess formed by onepression spring 1| interposed between the end of the control rod and theinner end of the detent plunger urges the latter into engagement withthe member 82.

As explained hereinbefore, the control rod is rocked beyond itsintermediate position when the tool head is fully retracted and isadapted under such conditions to actuate the auxiliary valve releasingswitch 8-2 and thus prepare the machine for the next operating cycle. Inthe particular organization shown, switch 8-2 is of the well knownspring actuated type which tends to move to an open position.Accordingly, the arcuate edge 88' of the cam 8| -is arranged to bearagainst a switch operating member 13 so as to hold the switch S-2 closedwhile the control rod is at any point between its forward limit positionand its intermediate position and thereby place the relay R-l undercontrol of the switch 8-! during this stage of an operating cycle. Anotch 14 cut in the edge of the cam is located so as to register withthe switch member I3 when the control rod is moved beyond theintermediate position, as shown in Fig. 6. When this occurs, the switchmember enters the notch, thereby opening the switch to deenergize theauxiliary valve operating solenoid SOL-2.

Referring now to Fig. 1, it will be observed that the opening of theswitch S2 in the manner above described interrupts the circuit of therelay R-l, assuming that switch S-l has been held closed as willgenerally be the case. Relay 55-! opens switch R-Il to deenergize thesolenoid SOL-2. The auxiliary valve V-B thereupon returns to normalposition and opens the hydraulic circuit between [the pilot valve V--4and reversing valve V3 so that the latter is immediately shifted toreverse position. The machine may now be stopped with the tool withdrawnfrom the work by operating the stop valve V2 in the usual way. Sincevalve V-3 has been shifted into a position corresponding with theposition of the pilot valve, the machine is in condition for the nextoperating cycle as the tool support will be moved forwardly when thepressure fluid is again supplied to the motor M.

When the rotatable control rod 33 is to be utilized for operating thepilot valve indirectly through the medium of solenoids SOL-3 and SOL-4,the operating mechanism 35 is replaced by the mechanism 38 shown inFigs. '7, 9 and 10 of the drawings. This mechanism comprises: anoperating member in the form of an elongated, generally rectangularblock 8! keyed or otherwise rigidly secured to the control rod.Projecting from opposite ends of the block substantially parallel to theaxis of the control rod are a pair of switch operating fingers 82 and 83adapted to cooperate respectively with reversing switches 8-3 and 8-4which control the reversal of the tool head at opposite ends of itsworking stroke aswill appear presently.

To provide control of the auxiliary valve V5, the operating finger 82 isextended to cooperate with a second switch 8-5. This is anormally closedswitch which performs the same function as the switch S2 previouslydescribed. The relative position of the switch S-5 and the operatingfinger is such that the switch is actuated upon rotation of the controlrod beyond its intermediate position incident to the movement of thehead to fully retracted position. switch 8-3,

accrue on the other hand, must be operated to closed position as thetool head reaches the rearward end of its working stroke at which timethe control rod is rocked to intermediateposition. Accordingly. thefinger 82 is provided with a yieldabie switch operator in the form of aplunger 84 (Fig. 9) slidably supported in a cylindrical recess 85 formedin a shoulder or boss 88 on the finger and extending generallytransversely of the axis of the control rod. Projecting from the innerend of the plunger 88 is an extension 81 of reduced diameter whichslides in an aperture at the rear of the recess 85 and serves to guidethe plunger in its movements of the recess. A coiled compression spring88 encircling the extension 81 and bearing respectively against the endwall of the recess and the inner end of the plunger urges the latter toa forward position determined by the setting of a stop nut 89 threadedon the projecting end of the extension 81. The normal position of theplunger 84 and thus the point at which it engages the operating member88 of the switch 8-3 may therefore be adjusted as required by turningthe nut 88.

Upon movement of the control rod and cam 8| to intermediate position,the plunger 84 engages the switch member 88 and closes the switch 5-3.Upon further movement of the control rod toward its limit position, theswitch is held closed but the plunger is forced into its recess againstthe action of the spring 88 so that no damage is done to the switchstructure. As the control rod approaches the rear limit position, thefinger 82 engages operating member 8i of the switch S-5 and opens thatswitch. When the control rod is rocked to its alternate limit positionupon movement of the tool support to the forward end of its workingstroke, the finger 83 engages the switch member 82 and closes the switch8-4.

The switches S3, S--8 and S-S are incorporated in a control circuit in amanner such that the momentary opening and closing of a switch iseffective to initiate the control function of that switch. After suchmomentary actuation, the switch is permitted to return to its normalposition by restoration of the control rod to neutral position. Suchrestoration of the control rod is efiected by means of spring-pressedplungers 38 as explained hereinbefore. In the modified operatingmechanism, the plungers 38 are disposed in sockets formed in the block8| on opposite sides of the control rod. As shown in Fig. 9, eachplunger 38 is formed with a reduced inner end portion slidably in anaperture in the block to guide the plunger in its movements in therecess. Stop nuts 98 threaded on the projecting end portions limit theforward movement of the plungers under the influence of compressionsprings 81 which yieldably urge the plungers outwardly into engagementwith the side of the machine frame I2. The point to which the plungersreturn the control rod may be readily adjusted by turning the adjustingnuts 96.

The manner in which the control switches, above described, areincorporated in the control circuit of a honing machine is showndiagrammatically in Fig. 11 of the drawings. In the operation of amachine so equipped, the pressure fluid pump motor M-i is started byclosure of a manually operable start switch 8-8 which completes acircuit for energizing a relay R-2. The relay R-2 completes a holdingcircuit for itself by closing its associated switch R.-2l and alsocloses a switch R-22 to connect the motor M-I across the line conductorsL-l, L2 and L-3 oi the power supply line SL. The motor may be stopped atany time by opening a normally closed stop switch S-l interposed in therelay holding circuit in series with the switch RPM.

It may be assumed that the stop valve V-2 is still closed after havingbeen operated to closed position to terminate the previous machinecycle. With the valve closed, the pressure fluid delivered by the pump Pwhich is driven by the motor M-i will be returned to the sump and nomovement of the tool head will take place at this time. The operation ofthe valve V-2 to terminate the machine cycle is effected by energizationof the solenoid SOL|. This solenoid is energized in response to theclosure of a manually operable switch 8-8 which completes an energizingcircuit for a relay R-5. The relay R-5 closes the switches R--5l andRf-52 to complete an energizing circuit for the solenoid.

When the tool head is to be reciprocated, the switch S-8 is opened,thereby deenergizing relay R-5 and solenoid SOL-i. The valve V--2accordingly returns to its normal position and directs pressure fluidthrough reversing valve V-3 to the motor M which drives the tool headforwardly on its guideway. As the tool head moves from its retractedposition it permits the control rod to move to neutral position, thusclosing the switch 8-5 and opening the switch S-3. The closure of theswitch 8-5 is ineffective at this time because switch S-i willbe in itsnormally open position. The opening of switch 5-3 will result in thedeenergization of relay R--3 which opens the circuit of the solenoid$L-3. The pilot valve V-fl, however, remains in its operated positionand forward movement of the head continues.

When the tool head reaches the forward end of its working stroke, thecam roller 43 engages the cam 52 and rocks the control rod.to itsforward limit position in the manner hereinbefore explained. In thisposition, the finger 83 of the switch operating mechanism operates toclose.

the switch S-fl. Switch 8-4 completes a circuit for a relay R-l whichenergizes and through the medium of switches RP-M and R42 completes anenergizing circuit for the solenoid SOL-4. Solenoid SOL-4 operates thepilot valve V -4 to its reverse position, thereby operating the valve V3and reversing the direction of movement of the tool head. Returnmovement of the head continues until the control rod is rocked to itsintermediate position by engagement of the cam roller 42 with the cam:52 as before explained. In the intermediate position of the control rodthe switch operating plunger 84 closes switch 8-3 which energizes relayR,-3 and solenoid SOL-43 to reoperate the pilot valve.

Reciprocation of the tool head through its working stroke continues withreversal automatically effected at each end of its stroke by alternateclosure of the switches S--3 and SB in the above manner. When the honingoperation is finished and the tool is to be withdrawn from the work,switch S| is closed manually, thereby energizing the relay RI. RelayRr-l in turn energizes solenoid SOL2 which operates the auxiliary valveV- and thus prevents reversal of the valve V--3 when the control rod isrocked to intermediate position in response to the tool head reachingthe rearward end of its working stroke. Accordingly, rearward movementof the head continues until the extreme limit of the withdrawal strokeis reached whereupon the switch 8-5 is opened in the manner previouslyexplained. Valve V-U is accordingly returned to its normal position andvalve V3 is reversed to initiate movement of the tool head in theopposite direction. Before such movement takes place, however, the toolhead may be stopped by closure of the valve V-2- either by manipulationof the control lever L or by actuation of the switch 8-8. The tool headis brought to rest with the tool withdrawn from the work so that thework piece may be removed and a new one substituted in its place.

It will be apparent from the ioregoing that the invention provides anovel and advantageous reciprocation controlling mechanism for honingmachines. The mechanism is quiet in action. reliable in operation,readily adjustable to adapt the machine for operating .on work pieces ofdifferent lengths and, by reason of its simple, rugged construction, iscapable of functioning accurately for long periods under the hard usageto which such mechanisms are necessarily subjected. The major portion ofthe mechanism may be utilized for either direct or indirect control ofthe reversing valve mechanism of the machine. Moreover, the improvedcontrol mechanism embodies novel means for facilitating thedisassociation of the tool and work upon completion of a honingoperation together with means for insuring proper operation of thereciprocating means in the next operating cycle of the machine.

I claim as my invention:

1. The combination in a honing machine having work and tool supports andpower actuated means for reciprocating one of said supports relative tothe other support to traverse the tool from one end of the work to theother, oifcontrol mechanism for said power actuatedmeans including arotatable control rod extending substantially parallel to thereciprocatory path of said one support, means on said one supportengageable with means on said rod for rocking the rod alternately intoeither of two angularly spaced positions as the support approachesrespective opposite ends of its working stroke, reversing means actuatedby said rod upon its operation to either of said positions to reversethe direction of movement of said one support, and auxiliary controlmeans operable to render said reversing means when actuated ineffectiveto reverse the direction of movement of said one support as the supportapproaches one end of its working stroke whereby to effect movement oithe support through an abnormally long stroke for dis-.

operated positions as the support approaches respective opposite ends ofits working stroke, a. control valve operated by said rod upon itsactuation to either of said positions for reversing said pressure fluidactuated means to reverse the direction of movement of said one support,an auxiliary valve operable to render said control valve ineffective toreverse the direction of movement of said one support at one end of theworking stroke whereby to initiate an abnormally long stroke of thesupport to disassociate the tool and work, and meansoperated by said onesupport tending substantially parallel to the reciprocatory path of saidone support, means on said one support engageable'with means on said rodfor rocking the rod alternately to either of two operated positions asthe support approaches respective opposite'ends of its working stroke, acontrol valve operated by said rod upon its actuation to either operatedposition for reversing said] pressure fluid operated means to reversethe direction of movement of said one support, an auxiliary valveoperable to render said control valve inoperative to efiect saidreversal whereby to "initiate an abnormally long stroke of said onesupport for disassociating the tool from the work,

. a solenoid adapted to be energized to operate said auxiliary valve, acircuit for said solenoid including a normally open switch and anormally closed switch, said first switch acting when closed to completethe circuit for energizing said solenoid, and means operated by saidcontrol rod upon movement of said one support to a predeterminedposition beyond the range of its working stroke to open said normallyclosed switch and thereby deenergize said solenoid.

4. In a honing machine, the combination of a reciprocatory support,pressure fluid operated means for reciprocating said support, controlmechanism for said pressure fluid operated means including a controlvalve operable to one position to eile'ct movement of the support in onedirection and to another position to effect movement of the support inthe opposite direction, means for operating said valve to said twopositions alternately comprising an elongated control rod extendingsubstantially parallel to the path of movement of the support, spacedmembers projecting radially from said rod for engagement by said supportto rock said rod alternately to two angularly spaced positions, .a camfast on said rod, an arm pivoted adjacent said rod and having a pair offollowers engaging said cam, said cam being shaped to move said armthrough a predetermined angle incident to the movement of said rodbetween said spaced positions, and a rigid link extending from said armto said valve to operate the valve.

5. In a honing machine, the combination of a reciprocatory support,pressure fluid operated means for reciprocating said support, controlmechanism for said pressure fluid operated means including a controlvalve operable to one position to effect movement of the support in onedirection and to another position to effect movement of the support inthe opposite direction, means'for operating said valve between saidpositions comprising an elongated control rod extending substantiallyparallel to the path of movement of the support, spaced members.projecting radially from said rod for engagement by said support to rocksaid rod into alternate active positions, a third member' projectingradially from'sai'd rod for engagement by the support to rock the rodbeyond one of said active positions, a' cam fast on the rod, an armpivoted adjacent the rod and having followers engaging said cam, saidcam being shaped to move said arm only through a predetermined anglewhen the rod is rocked between said active positions or beyond suchpositions, and a rigid link extending from said arm to said valve tooperate the valve.

6. In a honing machine, the combination of a reciprocatory support,pressure fluid operated means for reciprocating said support, controlmechanism for said pressure fluid operated means including a. controlvalve operable to one position to eflect movement of the support in onedirection and to another position to effect movement of the support inthe opposite direction, means foroperating said valve between saidpositions comprising an elongated control rod extending substantiallyparallel to the path of movement of the support, a cam on said rod,spaced members projecting'radially from said.'rod for-engagement by saidsupport to rock said rod into alternate active positions, a third memberprojecting radially from said rod for engagement by the support to rockthe rod beyond one of said active positions, a valve operating memberhaving means coacting with said cam and movable by the cam only to apredetermined position to operate said valve when the shaft is rockedbetween said active positions or beyond the same, and an auxiliarycontrol device Operated by said cam when the shaft is rocked beyond saidone active position.

7. In a honing machine, the combination of a reciprocatory support,pressure fluid operated means for reciprocating said support, controlmechanism for said pressure fluid operated means including a controlvalve operable to one position to effect movement of the support in onedirection and to another position to efl'ect movement of the support inthe opposite direction, means for operating said valve between saidpositions comprising an elongated control rod extending substantiallyparallel to the path of movement of the support, spaced membersprojecting radially from said rod for engagement by said support to rocksaid rod into alternate active positions, a cam fast on one end of saidrod, a valve operating member pivoted adjacent said rod and extendingover the face of said cam, followers on said member engageable by saidcam to rock the member to one or the other of its valve operatingpositions. and detent means carried by said cam for holding said memberin operated position independent of the engagement of the followers bythe cam.

8. A control mechanism for honing machines comprising, in combination, arotatable control rod, a cam fast on one end of said rod, a controlmember pivoted adjacent said control rod and extending over said cam,means on said member engageable by said cam upon rotation of the controlrod to operate the member to one or the other of two active positions,means for restoring the control rod and cam to a neutral position, andmeans for holding said member in operated position upon the return ofsaid cam to neutral position including a detent slidably mounted in theface of said cam coaxial with said control rod, and spring means tendingto force said detent into engagement with said member.

9. The combination in a honing machine having a power'drivenreciprocatory support, of control mechanism for controlling. thereciprocation of the support comprising, a rotatable control rodextending substantially parallel to the reciprocatory path of thesupport, means on said control rod engageable by the support in itsreciprocation through a predetermined range of travel for rocking thecontrol rod alternately to two active positions, a control deviceoperated under control of said rod in said active positions forreversing the direction of movement of the support, means fortemporarily rendering said device inefi'ective to reverse the directionof movement of the support and thereby initiate movement of the supportbeyond said predetermined range of travel, means on the control rodengageable by the support incident to said last mentionedmovement forrocking the control rod to a third active position, and a control deviceactuated by the control rod in said third active I position for againrendering said first mentioned control device effective to reverse thedirection of movement of the support.

10. The combination in a honing machine having a power drivenreciprocatory support, of control mechanism for controlling thereciprocation of the support including a control rod extending:generally parallel to the reciprocatory path of of the supportcomprising, a rotatable control rod extending substantially parallel tothe reciprocatory path of the support, means on said control rodengageable by the support in its reciprocation through a predeterminedrange of travel for rocking the control rod alternately to two activepositions, switches adapted to be actuated by the control rod in thefirst and second active positions respectively to reverse the directionof movement of the reciprocatory support, means for rendering one ofsaid switches temporarily ineffective to reverse the direction ofmovement of the support and thereby cause the support to move beyondsaid predetermined range of travel, means on said control rod engageableby the support incident tosaid last mentioned movement for rocking thecontrol rod to a third active position, and a switch actuated by the rodin said third activg position for reversingthe direction of movement ofthe support.

14. The combination in a honing machine having a power drivenreciprocatory support, of control mechanism for controlling thereciprocation of the support comprising, a rotatably supported controlrod extending substantially parallel to the reciprocatory path of thesupport, means on the support cooperating with means on the controlgenerally parallel to the reciprocatory path of the support, meanssupporting said control rod for rotation about its longitudinal axis,means on the control rod engageable by the support in its reciprocationfor rocking the control rod into alternate active positions, a valveoperable to either of two positions to reverse the direction of movementof the support, a pair of solenoids each adapted when energized tooperate said valve to one of its positions, a first switch arranged tobe actuated by the control rod in one active position for energizing oneof said solenoids, and a second switch arranged to be actuated by thecontrol rod in the other active position for energizing the other ofsaid solenoids.

12. The combination in a honing machine having a power drivenreciprocatory support, of control mechanism for controlling thereciprocation of the support comprising. a rotatable control rodextending substantially parallel to the reciprocatory path of thesupport, means on said control rod engageable by the support in itsreciprocation through a predetermined range of travel for rocking thecontrol rod alternately to two active positions, means on said controlrod engageable by said support incident to its movement beyond saidpredetermined range of travel for rocking the control rod to a thirdactive position, and separate control devices actuated by the rod ineach of said active positions.

13. The combination in a honing machine having a power drivenreciprocatory support, of control mechanism for controlling thereciprocation rod for rocking the rod to either of two limit positionsor to an intermediate position, a plurality of electrical switches forcontrolling the movements of the support, actuating mechanism carried bysaid control rod including a rigid member operable upon movement of therod to one limit position for operating one of said switches. a secondrigid member operable upon movement of the rod to the other of saidlimit positions for operating another of said switches, and a yieldablemember operable upon movement of the control rod to said intermediateposition for operating a third one of said switches, said last mentionedmember yielding to prevent damage to the switch upon movement of thecontrol rod beyond the intermediate position to one of said limitpositions.

15.' The combination in a honing machine having a power drivenreciprocatory support, of control mechanism for controlling thereciprocation of the support including a control rod extending generallyparallel to the reciprocatory path of the support, means supporting saidrod for rocking motion about its longitudinal axis, means yieldablyurging the control rod to a neutral position, cam means on the controlrod engageable by a member on the support in approaching one end of itsstroke for momentarily rocking the control rod into one active position,other cam means on the control rod engageable by said member as thesupport approaches the other end of its stroke for momentarily rockingthe control rod into an alternate active position, means actuated by thecontrol rod incident to its movement into either active position forreversing the direction of movement of the support, and means formaintaining the effectiveness of said reversing means after the controlrod is returned to neutral position.

16. The combination in a honing machine having a power drivenreciprocatory support, of confor rocking the control rod into alternateactive positions, a control device operable in response to movement ofthe control rod into either active position to reverse the direction ofmovement of the support, means for temporarily rendering said deviceinactive to reverse the direction 01 movement of the support when thecontrol rod is rocked into one of its active positions, said supportmoving beyond its normal range of travel, and means actuated by thecontrol rod upon movement of the support to a predetermined position fordisabling said last means to again render said device efiective toreverse the direction of movement of the support.

17. A control mechanism for honing machines having a reciprocatorysupport and power actuated means for reciprocating the support, saidcontrol mechanism comprising, in combination, an elongated control rodsupported to rock about its longitudinal axis, means yi'eldably holdingsaid rod in a neutral position, means for momentarily rocking said rodin either direction from said neutral position, a cam on said rod, acontrol member movable by said cam incident to the rocking of thecontrol rod in either direction, detent means for holding said member ineither operated position upon the return of the control rod to neutralposition, and means operated by said member for controlling the poweractuated support reciprocating means.

18. A control mechanism for a honing machine having a reciprocatorysupport and hydraulically actuated means for reciprocating the support,said control mechanism comprising, in combination, a valve forcontrolling the hydraulically actuated support reciprocating means, acontrol rod supported for rocking movement, means yieldably holding saidrod in a neutral position, means for momentarily rocking said rod ineither direction from saidneutral position, a cam on said rod, a controlmember movable by said cam into either of two positions incident to therocking of said control rod, detentmeans for holding said member ineither active position upon the return of the control rod to neutralposition, and

means providing a mechanical connection between said member and saidvalve.

HARRY J. CALDWELL.

